Charging systems for electric vehicles

ABSTRACT

This disclosure provides systems and methods for charging a vehicle. A vehicle and charging station can be designed such that an electric or hybrid vehicle can operate in a fashion similar to a conventional vehicle by being opportunity charged throughout a known route.

CROSS-REFERENCE

This application is a continuation application of U.S. patentapplication Ser. No. 12/496,569 filed on Jul. 1, 2009, which claimspriority to U.S. Provisional Application No. 61/077,452 filed on Jul. 1,2008, and U.S. Provisional No. 61/174,926 filed on May 1, 2009, whichapplications are incorporated herein by reference in their entirety.

STATEMENT AS TO FEDERALLY SPONSORED RESEARCH

This invention was made with the support of the United States governmentunder the National Fuel Cell Bus program, Project ID numbers GA-04-7001and GA-04-7002 awarded by the Federal Transit Administration (FTA). Thegovernment has certain rights in the invention.

BACKGROUND OF THE INVENTION

Electric vehicles are limited by current infrastructure for transferringpower to the electric vehicles. Some electric vehicles, such as electrictrains and light rail cars, are permanently connected to a power sourcethrough hardware in the railing or through overhead lines. Otherelectric vehicles, such as electric cars, are charged by plugging in theelectric vehicle at a charging station.

While systems for maintaining a permanent electrical connection along aroute taken by an electric vehicle can be used to transfer power to theelectric vehicle, these systems are an eyesore, are unpopular, arecostly to install and maintain, and can be unsafe. These systems oftenrequire the entire electric bus line to be suspended for periods of timewhile cities perform routing building maintenance or construction. Someof these systems do not enable an electrical vehicle to run independentof a railing or overhead line. Also, some of these systems are notadaptable to different vehicles with different characteristics.Furthermore, these systems may take a significant amount of time oreffort to charge.

Thus, there is a need to develop improved systems and methods forcharging electric vehicles.

SUMMARY OF THE INVENTION

The invention provides systems and methods for charging an electric orhybrid electric vehicle. Various aspects of the invention describedherein may be applied to any of the particular applications set forthbelow or for any other types of vehicles. The invention may be appliedas a standalone system or method, or as part of an integratedtransportation system, such as a bus system or other publictransportation system. It shall be understood that different aspects ofthe invention can be appreciated individually, collectively, or incombination with each other.

One aspect of the invention may be directed to a charging station. Acharging station may include a charging mount. A charging station mayalso include two or more collector braces, where each collector braceincludes at least one electrically conductive surface area, such as aconductive pad. Preferably, each collector brace may include at leasttwo guiding strips with electrically conductive surfaces where guidingfeatures on the strip, such as guiding pads, converge such that theconvergence is directed toward the electrically conductive surfaces. Atleast one collector brace may be for contacting a positive electrode andat least one collector brace may be for contacting a negative electrode,which may be configured to charge a rechargeable device of a vehicle. Acharging station may include support fixtures such as a post connectedto the charging mount and a stand mechanically connected to the post forsupport the post and charging mount.

In accordance with another embodiment of the invention, a chargingstation may include a charging overhang with rigid structural componentsthat is mounted to a charging mount. The charging overhang may includerigid components such as a crossbar, spacing bar, and one or more arms.Rigid or flexible connections may be provided between the rigidcomponents. For example, collector braces on the charging overhang maymove relative to the crossbar of the overhang, through a flexibleconnection.

Another aspect of the invention may be directed to a vehicle, which maybe charged by a charging station. The vehicle may include two or morecontact plates electrically connected to a rechargeable device of thevehicle. The rechargeable device of the vehicle may be an energy storagesystem, such as a battery or ultracapacitor. The contact plates may belocated on top of the vehicle, and may be positioned relatively parallelto a direction of movement for the vehicle. They may also be spacedapart on the top surface of a vehicle. A first contact plate may be apositive electrode and while a second contact plate may be a negativeelectrode to charge the rechargeable device.

A system for charging a vehicle may be provided in accordance withanother embodiment of the invention. The system may include a chargingstation with two or more collector braces and a vehicle with two or morecontact plates. The collector braces may be configured to receivecontact plates on top of the vehicle such that the contact plates slidebetween electrically conductive surfaces after being guided by guidingstrips. The contact plates may be squeezed between the guiding strips toensure good electrical contact. Furthermore, the electrically conductivesurfaces may have a surface area that contacts the contact plates, whichmay provide an area of electrical contact. Such features may decreaseimpedance at the charging interface between the charging station andvehicle, which may aid in fast charging. The charging station may alsoinclude a spacing bar to keep the collector braces at a desired distanceapart from one another, which may match the distance between the contactplates of the vehicle. The charging station may also include a flexibleconnection for a connecting structure that connects the charging mountand collector braces, which may enable the connecting structure andcontact assemblies to move laterally with respect to the direction ofvehicle travel. This may provide tolerance for vehicle dimensions, drivepath, or other vehicle attributes.

A method for charging a vehicle may be provided in accordance withanother embodiment of the invention. The method may include moving avehicle comprising two or more contact plates to a position below acharging mount of a charging station, where the charging mount has twoor more collector braces. An electrical connection may be establishedbetween the two or more collector braces and the two or more contactplates of the vehicle. The vehicle may remain electrically connected toa charging station for a period of time to achieve a desired state ofcharge.

Other goals and advantages of the invention will be further appreciatedand understood when considered in conjunction with the followingdescription and accompanying drawings. While the following descriptionmay contain specific details describing particular embodiments of theinvention, this should not be construed as limitations to the scope ofthe invention but rather as an exemplification of preferableembodiments. For each aspect of the invention, many variations arepossible as suggested herein that are known to those of ordinary skillin the art. A variety of changes and modifications can be made withinthe scope of the invention without departing from the spirit thereof.

INCORPORATION BY REFERENCE

All publications, patents, and patent applications mentioned in thisspecification are herein incorporated by reference to the same extent asif each individual publication, patent, or patent application wasspecifically and individually indicated to be incorporated by reference.

BRIEF DESCRIPTION OF THE DRAWINGS

The novel features of the invention are set forth with particularity inthe appended claims. A better understanding of the features andadvantages of the present invention will be obtained by reference to thefollowing detailed description that sets forth illustrative embodiments,in which the principles of the invention are utilized, and theaccompanying drawings of which:

FIG. 1 shows a charging station in accordance with an embodiment of theinvention.

FIG. 2 shows an alternate embodiment of a charging station.

FIG. 3 shows another embodiment of a charging station.

FIG. 4 shows an example of a charging station.

FIG. 5 shows an example of a charging connection of a charging station.

FIG. 6A shows a view of a contact assembly.

FIG. 6B shows an additional view of a contact assembly.

FIG. 6C shows a close up of a pressure assembly in accordance with anembodiment of the invention.

FIG. 7A shows a contact assembly on a charging mount.

FIG. 7B shows an example of a flexible connection of a connectingstructure.

FIG. 8 shows an example of a vehicle with a contact bar.

DETAILED DESCRIPTION OF THE INVENTION

The invention provides for systems and methods for charging an electricvehicle. One aspect of the invention provides for a charging station.The charging station can be used to transfer power to an electricallypowered vehicle. The charging station may be used to transfer power toany electric vehicle, hybrid electric vehicle, or any other vehicle thatmay include a propulsion power source, such as a battery,ultracapacitor, or any other energy storage system. In some embodiments,an electrically powered vehicle may be a heavy duty vehicle, such as abus or truck.

For example, electrical vehicles powered by the system may include atransit bus, a school bus, a delivery van, a shuttle bus, a tractortrailer, a class 5 truck (weighing 16,001-19,500 lbs., two-axle,six-tire single unit), a class 6 truck (weighing 19,501-26,000 lbs.,three-axle single unit), a class 7 truck (weighing 26,001-33,000 lbs.,four or more axle single unit), a class 8 truck (weighing 33,000 lbs.and over, four or less axle single trailer), a vehicle with a GVWRweighing over 14,000 pounds, a vehicle with a cargo to driver mass ratioof 15:1 or greater, a vehicle with six or more tires, a vehicle withthree or more axles, or any other type of high occupancy or heavy-dutyvehicle. In some embodiments, a charging station may charge any otherelectric vehicle, including passenger vehicles. Any discussion herein ofelectric vehicles or electrically powered vehicles may refer to any typeof vehicle discussed and vice versa.

In some embodiments of the invention, the charging station can comprisea charging connection, such as a charging chassis or overhang, suspendedfrom a charging mount for establishing an electrical connection betweenthe charging station and the electrically powered vehicle. The chargingconnection can comprise a positioning device for controlling theposition or orientation of the charging connection.

Another aspect of the invention provides for an electric vehiclecomprising contact plates for establishing an electrical connection to acharging station. The contact plates can be positioned on a top surfaceof the electric vehicle and be positioned in a direction that isrelatively parallel to a direction of vehicle movement. The contactplates may be spaced apart on the top surface of the electric vehicle.

The methods of the invention include transferring power to a vehicleusing a charging station. Transferring power to the vehicle can comprisepositioning the vehicle under a charging mount of the charging stationand engaging a charging connection, such as a pantograph, catenary arm,charging chassis or frame, or charging overhang to establish anelectrical connection between the charging station and the vehicle.

As shown in FIG. 1, the charging station can comprise a structure (6)with a charging mount (24). A charging connection (18) can be suspendedfrom the charging mount. The charging connection can be a device similarto a components selected from the group consisting of a pantograph, acatenary arm, and a cantilever arm. The charging connection can have anadjustable shape or size such that an electrically conductive surface(14, 16) located on the charging connection can have an adjustablelocation. In some embodiments of the invention the charging connectionis mechanically attached to the charging mount through a coupling, suchas a positioning device (20, 26). The positioning device can be fixed oradjustable.

In some embodiments of the invention the charging connection cancomprise two electrically conductive surfaces (14, 16), such asconductive pads. The two electrically conductive surfaces can beelectrically insulated from each other. The two electrically conductivesurfaces can be supplied power through electrical wiring thatelectrically connects the electrically conductive surfaces to a powersource (2). The electrical wiring can be housed within the chargingconnection (18), positioning device (20, 26), the charging mount (24),and the structure (6). Additional electrical wiring (4) can be used toestablish an electrical connection to the power source (2). The powersource can comprise any power source described herein.

As shown in FIG. 1, the vehicle (8) can comprise two contact plates orbars (10, 12) extending in a direction of vehicle movement (28). The twobars can be copper bars that are electrically connected to an energystoring device used to power the vehicle.

An alternate embodiment of the charging station is shown in FIG. 2. Theelectrically conductive surfaces (14, 16) can be connected to thecharging mount through a cantilever arm (30). The cantilever arm can beadjusted in a vertical direction (22) to allow a vehicle (8) to passunder the conductive surfaces and then for establishing an electricalconnection between the conductive surfaces and contact plates or bars(10, 12) on the vehicle. The electrical connections between theconductive surfaces and the power source (2) can be as described in FIG.1.

FIG. 3 shows another example of a charging station (36) and a vehicle(38). The vehicle may include one, two, three, four or more chargepoints, which may be contact bars, plates, or contacts of any othershape. In some embodiments, it may be preferable to have at least twocharge points. In other embodiments, larger numbers of charge points maybe desirable to charge multiple batteries (e.g., two charge points maybe electrically connected to one battery or group of batteries, anothertwo charge points may be electrically connected to another battery orgroup of batteries). Charging multiple battery sets in parallel may bedesirable to speed up charge time and reduce system heating due to highcurrent transfer. Any discussion of charge points or any other contactsmay refer to contacts of any shape or format.

Charge points (40 a, 40 b) may extend parallel to the direction ofvehicle movement. In preferable embodiments of the invention, the chargepoints may be mounted on top of the vehicle, such as on the roof of thevehicle. In some alternate embodiments, the charge points may be mountedon a side of a vehicle, in the roadway, or along another portion of thesurface of the vehicle, or combinations thereof. As discussedpreviously, the charge points may be formed of copper. In someembodiments, the charge points may be formed of any conductive material,including but not limited to aluminum, silver, gold, or alloys orcombinations thereof, and/or may be plated or clad with any conductivematerial including but not limited to copper, aluminum, silver, gold,alloys or combinations thereof, or any other conductive material. Thecharge points may be electrically insulated from one another. The chargepoints may be spaced apart from one another on top of the vehicle.

The charging station (36) may include any number of contact assemblies(42 a, 42 b), such as collector braces. The contact assemblies may beelectrically connected to charge points of a vehicle, which may functionas electrodes. In some instances, the number of contact assemblies maymatch the number of charge points (40 a, 40 b) on the vehicle. Forexample, if two charge points are provided on the vehicle, two contactassemblies may be provided on the charging station. If four chargepoints are provided on the vehicle, four contact assemblies may beprovided on the charging station.

In some embodiments, a pair of contact assemblies may be provided tomake contact with a pair of charge points connected to a battery orbattery pack. In some instances, more contact assemblies may be provided(e.g., two contact assemblies may contact a pair of charge points whichare in electrical communication with a battery or group of batteries,while two other contact assemblies may contact two other charge pointswhich are in electrical contact with another battery or group ofbatteries). Charging multiple batteries at the same time may bedesirable to speed up charge time and reduce system heating due to highcurrent transfer. In some instances, the multiple contact assemblies maybe provided on the same arm of a charging station (e.g., four contactassemblies may be provided on the same overhang), while in otherinstances the multiple contact assemblies may be provided on a pluralityof arms of a charging station (e.g., two contact assemblies may beprovided on one overhang, while two contact assemblies are provided on asecond overhang).

The contact assemblies may include one or more guiding feature (44 a, 44b, 44 c, 44 d) that may assist with guiding the charge points to contactconductive pads of the contact assemblies.

Charging Stations

A charging station can comprise a charging mount positioned above theground and a charging connection suspended from the charging mount. Thecharging connection can be directly attached to the charging mount orattached to the charging mount through a coupling, such as a positioningdevice. The charging connection can be similar to a device selected fromthe group consisting of a pantograph, a catenary arm, and a cantileverarm. The charging connection may include, or also be referred to as, acharging chassis or frame, a charging skeleton or girder, or a chargingoverhang. The charging connection can be an inverted form of a deviceused to power a light rail car or an electric bus. In other embodimentsof the invention, the charging connection is a catenary arm suspendedfrom the charging mount. The catenary arm can be supported by acantilever arm.

In some embodiments, the charging can be for a two wire trolley bus suchthat the bus can operate as a trolley bus. For instance, for part of thetime, a bus may be operating as a trolley bus by connecting to wires ona grid system. When the bus reaches the end of a grid system, trolleypoles may be lowered and the bus may operate as a battery electric bus,independent of the grid. Similarly, a battery electric bus may operateindependent of the grid and then encounter the grid. When the busreturns to the grid, the poles may be raised into contact with the gridand the bus may be recharged while operating as a trolley bus. Thus, inaccordance with an embodiment of the invention, a bus may operate on thegrid part of the time and off the grid part of the time. The bus mayoptionally use the on-grid time to charge the batteries on the bus,which may be used when the bus is off-grid.

The charging connection may have a sensor or a mechanical orelectro-mechanical height adjustment system to allow the chargingconnection to adjust to a height required to allow a vehicle to driveunder the charging connection. The system for height adjustment caninclude the charging connection and/or the positioning device. Thecharging connection can be adjusted to a height required to establish anelectrical connection.

The electrical connection can be established for a time sufficient tocharge the vehicle partially or fully. The charging connection can bedesigned in such a fashion that it is only activated when an electricalconnection is made between the vehicle and the charging station and/or asignal is received from the vehicle to activate charging. The chargingstation can comprise mechanical and/or electrical protective devices toisolate conductive paths during non-contact situations. Such devices maybe configured to allow energy flow only after receiving an electronicmessage (wireless, proximity switched contact, and/or manual trigger) orvia direct mechanical activation.

In alternate embodiments, if the vehicle were to operate part timeon-grid as a trolley, energy flow may automatically occur when thevehicle reaches the grid. In some embodiments, a sensor may be providedthat may allow the energy flow, while in other embodiments, mechanismsmay be provided that may enable energy flow when the vehicle reaches thegrid. Safety features may be provided, which may allow energy flow onlyin a desired manner.

In another embodiment the vehicle (e.g., bus) can adapt to existinglight rail systems, where the vehicle is able to connect to the singleoverhead line and the ground coupling in the roadway rail.

Power can be supplied to the charging connection using any means knownto those skilled in the arts. In some embodiments of the invention, anelectrical power source used to power an electric vehicle such as alight rail or an electric bus can be used. The electrical power sourcecan be a power source used to supply power to an overhead line forpowering an electric train or a bus. The electrical power source cancomprise a high voltage DC power source. The voltage can be between 400and 800 volts DC, between 450 and 750 volts DC, or approximately 600volts. The power source can be tapped and then transferred to a voltageconverter to provide the correct voltage and current flow for thevehicle. The voltage converter can be a DC-DC charger. In otherembodiments of the invention, a rapid charger can be used to supplypower to the charging connection. The rapid charger can be powered byconventional power sources or alternative power sources. In someembodiments of the invention, the rapid charger is powered by hydrogen,conventional electricity obtained from a power grid, or any other typeof power source. The rapid charger can be configured to provide avoltage and current to a vehicle.

The power supply can comprise an energy buffer device. The energy buffercan be a capacitor or a battery. The capacitor can be a largeultra-capacitor. The battery can comprise a battery pack. Use of such asystem may allow for off-peak charging of the energy buffer device atlower energy costs, then supply some or all of the daytime energy needsof the charging station. This energy buffer device may also allow theuse of lower power infrastructure and/or charging supplies. The energybuffer device may allow for a slow charge of the energy buffer overtime, then allow for rapid energy delivery through the chargingconnection.

The energy buffer device can be utilized for utility grade emergencypower or load balancing on a utility grid. Because the energy bufferdevice may be incorporated into large buildings for emergency power orinto the utility grid for power balancing, the system can havecross-functionality and can be a joint project for customers of theservices.

The charging station can be located at a hub or any position along theroute of a vehicle. In other embodiments of the invention, the chargingstation is located near an overhead line or an electric railway used topower a light rail vehicle, a train, or an electric bus.

FIG. 4 shows an example of a charging station in accordance with anembodiment of the invention. The charging station may comprise astructure (50) with a charging mount (51). The charging mount maycomprise a charging connection (52). The charging connection may hangbelow the charging mount. The charging connection may extend downwardand/or away from the charging mount.

In some embodiments, the charging connection (52) may be connected to acharging mount (51) via a coupling (55). The coupling may be fixed oradjustable. For example, the coupling may be adjustable so that acharging connection may move vertically with respect to the chargingmount. For instance, the coupling may be a vertical post with a flexiblemember such as a spring, an elastic component, a pneumatic device, amagnet, a weight or a gear. The flexible member may enable the chargingconnection to have a default height which may be adjustable when a forceis exerted on it. For example, if a vehicle is passing under thecharging connection and encounters a bump, the charging connection mayaccommodate the bump and maintain electrical contact with the vehicle.Similarly, when vehicles of slightly different height pass under thecharging connection, they may be accommodated by a flexible coupling.This may be advantageous in situations where vehicle height may vary dueto factors such as tire pressure or load weight.

In some alternate embodiments, the coupling may allow for activeadjustment of charging connection height, which may allow the chargingstation to accommodate vehicles of a wide range of heights. For example,a sensor may be in communication with the coupling to inform thecoupling of an incoming vehicle's height.

The charging connection may include one or more contact assemblies (53a, 53 b). In some embodiments, a contact assembly may include a pair ofguiding strips. A contact assembly may include one or more electricallyconductive surfaces, such as a conductive pad, that may make electricalcontact with a charge point. In some embodiments, a contact assembly mayinclude two conductive pads that may make electrical contact with acharge point. The charging structure and charging mount may have anystructure or form that may enable the contact assemblies to contact thecharge points of a vehicle. For example, a charging mount may form ahorizontal post or cantilever extending from the charging structure.

In some embodiments, the charging structure (50) may include a verticalpost. Alternatively, the charging structure may have any other shape orconfiguration that may support the charging mount and/or chargingconnection at a desired height. The charging structure could even bepart of a wall or pre-existing structure such as a bus stop waitingstation. In some embodiments, the length of the charging structure maybe adjustable, which may result in the position of the chargingconnection being adjustable. The charging structure may be passivelyadjustable, such as if a vehicle passes beneath the charging connection,and causes the charging structure to accommodate the height of thevehicle. The charging structure may also be actively adjustable, such asif the vehicle approaching the charging station emits a signalindicating the vehicle type or height, so that the charging station mayadjust its height to accommodate the incoming vehicle.

In some instances, the charging mount and structure may keep electricalconnections from each of the contact assemblies segregated. For example,electrical connections from two contact assemblies may be segregatedwithin a single integrated structure (e.g., a single pole), or thestructure may include two components (e.g., two poles) that may houseelectrical connections for each of the contact assemblies. In someimplementations, the charging mount and structure may keep electricalconnections from each of the conductive pads within a contact assemblysegregated.

The charging station may also include a stand (56). The stand mayprovide structural support to a charging structure (such as a post) anda charging mount/charging connection. In some embodiments, the stand maybe located at or form the base of a support structure of a chargingstation.

The charging station may also include a power source (54). As discussedpreviously, the charging station may be powered by conventional powersources or alternative power sources.

FIG. 5 shows a view of the charging connection. The charging connectionmay form a charging chassis, charging frame, or charging overhang. Thecharging connection may include contact assemblies (60 a, 60 b). Eachcontact assembly may include one or more guiding feature (61 a, 61 b, 61c, 61 d), such as a guiding strip or guiding slat, that may assist withforming an electrical contact between a charge point on a vehicle andthe contact assembly.

The contact assemblies may be spaced at a desired distance apart. Forinstance, two or more contact assemblies may be spaced at any desireddistance apart. For example, the contact assemblies may be spaced about5 cm, 10 cm, 15 cm, 20 cm, 25 cm, 30 cm, 35 cm, 40 cm, 45 cm, 50 cm, 60cm, 70 cm, 80 cm or greater or lesser apart. Preferably, the contactassemblies may be spaced at a distance apart that is substantially thesame as or closely approximates the distance between charge points on anapproaching vehicle.

The charging connection may also include a structure or feature that maykeep the contact assemblies at a predetermined distance apart. Forexample, a spacing bar (62) may be provided which may keep the contactassemblies (60 a, 60 b) at a predetermined distance apart. Thepredetermined distance may correspond to the distance between the chargepoints on the roof of the vehicle. The predetermined distance may befixed, such that the contact assemblies remain at the same distanceapart. Alternatively, the predetermined distance may be flexible. Forexample, a spring or elastic feature may be provided within the spacingbar (62) such that the spacing bar is a predetermined distance apart atrest, but when force is exerted along the length of the spacing bar, thelength of the spacing bar may compress or expand slightly. Such featuresmay enable vehicles with charging points that may be at slightlydifferent distances apart to approach a guiding feature, and then havethe spacing bar adjust its length to accommodate the charging pointssliding through the contact assemblies (60 a, 60 b).

In another example, the spacing bar may include features that may enablethe length of the spacing bar to be adjusted as desired. For example,different vehicles may have charging points that are spaced apart atdifferent distances. The vehicles may provide a signal to a chargingstation about the distance between the charging points, so that thecharging station can adjust the length of the spacing bar to accommodatethe charging point distances. A sensor or a hydraulic, mechanical orelectro-mechanical length adjustment system for the spacing bar may beutilized. This may be useful in situations where different makes ormodels of vehicles may be conductive to charging points being spaced atdifferent distances apart. Any discussion herein of the spacing bar mayalso apply to any other structure or component that may provide contactassemblies with a fixed or variable/controllable distance between oneanother.

The charging connection may also include a positioning bar (64). In someembodiments, the positioning bar may be a horizontal bar, which may beconnected to a coupling (66), which is connected to a charging mount.Alternatively, the positioning bar may be directed connected to acharging mount. In some embodiments, the positioning bar may be a rigidmember of the charging connection. The charging connection may alsoinclude one or more arms (65 a, 65 b) extending from the positioningbar. The arms may be connected to the contact assemblies and/or thespacing bar. In some instances, the arms may extend downward from thepositioning bar and/or horizontally away from the positioning bar. Insome instances the arms may extend both downward and away from thepositioning bar. Preferably, the arms may be rigid members. The arms maybe connected to the positioning bar through a flexible connection or arigid connection. Similarly, the arms may be connected to the contactassemblies and/or spacing bar through a rigid connection or a flexibleconnection. The positioning bar, spacing bar, and one or more arms mayform a chassis or frame for a charging connection. A charging connectionwith rigid members and one or more flexible connection may form asemi-rigid structure. The semi-rigid charging connection mayadvantageously provide enough structure and rigidity to orient thecontact assemblies to accept charge points from a vehicle, whileproviding enough flexibility to accommodate variations in charge pointplacement or vehicle drive orientation.

The charging connection may also include wires (63 a, 63 b, 63 c, 63 d)or other electrical connections that may be provided from conductivepads. For example, electrical connections between each of the contactassemblies may be segregated. In some instances, electrical connectionsbetween each of the conductive pads may be segregated.

In preferable embodiments of the invention, the contact assemblies maybe at substantially the same height. This may accommodate vehicles wherethe charge points of the vehicles are at substantially the same height.In some alternative embodiments, the contact assemblies may be arrangedsuch that they are at different heights (e.g., 60 a may hang lower than60 b), which may accommodate vehicles where the charge points are atdifferent heights (e.g., one contact plate may extend from a vehicleroom higher than another).

FIG. 6A shows a view of a collector brace, which may also be referred toas a contact assembly, and vice versa. The collector brace may include aguiding feature, such as a guiding strip (70 a, 70 b). The guidingfeature may be shaped such that it may capture a charging point, andguide it to one or more contact pads (71 a, 71 b). A pair of guidingfeatures may form a ‘V’ shape to capture the charging point, or may haveany other shape, such as a “U” shape, or any shape that may have alarger opening that may funnel or guide the charge point to a smalleropening. The guiding features may start off at some distance apart, andthen they may converge toward one another at electrically conductivesurfaces of the guiding features. This funneling aspect may enable theguiding features to have some tolerance in capturing the charge pointsfrom a vehicle. The charge points may be captured at the wide end of thefunnel, and be directed toward the electrically conductive surface,which may be spaced closer together.

A guiding feature may include an electrically conductive surface, whichin some embodiments may be a contact pad. The contact pads (71 a, 71 b)may be metallic or non-metallic conductive pads and may or may not bereplaceable. A preferable method would be to have replaceable pads thatcan be changed when the conductive portion is damaged or used. In oneexample, the contact pads may be conductive carbon pads. Part of thecarbon pads may scrape off whenever a charge point slides between thecontact pads. In such instances, the carbon pads may be replaceable. Inother embodiments, any other conductive materials (such as metals, ormetal alloys) may be used. Preferably, the contact pads may be formed ofa slippery material that may enable the charge points to slide througheasily.

In some embodiments, two or more contact pads may be provided percollector brace. In other embodiments, only one contact pad may beprovided per collector brace. Different collector braces may or may nothave the same number of contact pads. A charge point may slide betweenthe electrically conductive surfaces of the collector brace, such thatthe charge point is sandwiched between the electrically conductivesurfaces, such as the contact pads. Preferably when the charge point isbetween the electrically conductive surfaces, the charge point iscontacting both contact pads.

In some embodiments, the contact pads may provide an electricallyconductive surface area. In some embodiments, the electricallyconductive surface area may be 1 sq. cm, 2 sq. cm, 4 sq. cm, 6 sq. cm, 8sq. cm, 10 sq. cm, 12 sq. cm, 15 sq. cm, 20 sq. cm, 25 sq. cm, 35 sq.cm, 50 sq. cm or greater.

The contact pads may have any shape, such as rectangular, square,circular, oval, triangle, trapezoidal, hexagonal, etc. The contact padsmay also have any dimensions. For example, the contact pads may be 0.5cm long, 1 cm long, 2 cm long, 4 cm long, 6 cm long, 8 cm long, 10 cmlong, 12 cm long, 15 cm long, 20 cm long, 25 cm long, 30 cm long, 35 cmlong, 40 cm long, 50 cm long, or longer. Similarly, the contact pads maybe 0.5 cm wide, 1 cm wide, 2 cm long, 4 cm wide, 6 cm wide, 8 cm wide,10 cm wide, 12 cm wide, 15 cm wide, 20 cm wide, 25 cm wide, 30 cm wide,35 cm wide, 40 cm wide, 50 cm wide, or wider. In some embodiments, thecontact pads may be longer than they are wide.

In some embodiments, the contact pads may be of a sufficient width toprovide leeway in the height of the charge points of a vehicle. Forexample, if the contact pads have a significant width, they may stillcontact the charge points of a vehicle, even if the vehicle is slightlyshorter or taller than average. The charge points may end up contactingthe contact pads toward the top of the contact pads or toward the bottomof the contact pads. Thus, having a substantial surface area to acontact pad may be advantageous in accommodating different vehicleheights, or irregularities in heights of the vehicle that may appearfrom different features of the terrain, such as bumps in the road.

In some embodiments, the charging station may include a horizontalroller, or similar feature, which may make preliminary contact with theroof mounted charge points (e.g., copper bars) to adjust the height. Thehorizontal roller, or any other guiding mechanism may be used to makecontact with the roof of a vehicle, and provide a reference or guidethat may enable the contact pads of the charging station to achieve adesired height. For example, if the vehicle-mounted charge points areabout a couple of inches above the vehicle roof, a height guide, such asa roller may be provided several inches below the contact pads, so thatwhen the roller contacts the roof of the vehicle, the height of thecontact pads may be adjusted to be at the desired charging height. Ahorizontal roller may contact the roof of the vehicle, and roll over theroof of the vehicle, which may enable the vehicle to pass underneathwithout cause any damage to the vehicle. Other comparable mechanismsknown in the art may be used, such as a guide that may have a softslippery surface that may brush over the vehicle roof.

In some embodiments, the entire electrically conductive surface area ofthe contact pad may be contacting a charge point, such as a side of acontact plate on a vehicle. In preferable embodiments, the surface areacontact at the interface between the collector brace of the chargingstation and the charge point of vehicle may provide increasedconductivity and electrical flow between the charging station and thevehicle, which may enable a battery of the device to be fast-charged.

The vehicle may receive a signal when the contact plate on the vehiclemakes contact with the contact pad or comes within a collector brace, inaccordance with an embodiment of the invention. That signal may takecommand of the bus and cause it to stop. If the bus were to stop whenmaking electrical contact, the contact plates on the bus would not haveto be very long. This may advantageously provide less exposure to anelectrically “hot” area.

Thus, it may be advantageous to provide a pair of collector braces and apair of charge points, so that each collector brace has an electricallyconductive surface on both sides of a charge point, such that thesurface area connection between the charge point and the collector braceis increased.

The guiding features may also include guiding pads (72 a, 72 b, 72 c, 72d). The guiding pads may be formed of a slippery material that mayenable charge points to slide through. In some embodiments, a polymer orplastic may be used for the guiding pads. For example, the guiding padsmay be formed of a nylon. In some instances, the guiding pads mayinclude a coating or be clad with a slippery material.

In some embodiments, the guiding pads may be very long, or the contactpads may have a cover extending both fore and aft. The cover may be longenough to ensure that the charge bar on the roof is covered duringcharging. This may prevent a large bird or something similar from makingcontact between the two charge bars.

The contact pads (71 a, 71 b) may be electrically connected to a powersource. In some instances, the contact pads may be electricallyconnected through wires (73 a, 73 b).

In some embodiments, a charging station may include a pair of collectorbraces, or more. In some instances, at least one collector brace may befor providing an electrical connection with an anode while at least oneother collector brace may be for providing an electrical connection witha cathode, when the collector braces contact the charge points of avehicle. If there are more than one contact pads in a collector brace,the contact pads may function may be for contacting the same type ofelectrode. For example, two collector braces may be provided, eachcomprising two contact pads. Both contact pads in one contact assemblymay contact an anode, while both contact pads in the other contactassembly may contact a cathode. In some implementations, differentcontact pads within the same contact assembly may contact differentelectrodes. For instance, one collector brace may be provided, and onecontact pad may contact a cathode while another may contact an anode.

A collector brace may also include a casing (74). In some instances, acasing may provide support or structure to the collector brace. In someembodiments, a pressure assembly (75) may be provided that may exertforce on one or more guiding feature (70 a). In some instances, thepressure assembly may exert force on one guiding feature, while theother guiding feature may be fixed. In another instance, two pressureassemblies may be provided, whereby each pressure assembly exerts aforce on a guiding feature. The force exerted on a guiding feature maybe directed toward another guiding feature. For example, if a pair ofguiding features beside one another is provided, one of the guidingfeatures (e.g., 70 a) may have a lateral force directed to the otherguiding feature (e.g., 70 b), such that the guiding features would havea squeezing force. By doing so, the contact pads of each guiding featureis pressed to the charge point when the charge point passes through,which ensures that an electrical connection is made. Furthermore, aspreviously discussed, by using a large surface area for the contactpads, a large surface area electrical interface may be provided betweenthe contact pads and the charge points. By exerting a sufficient amountof pressure on the connection, the large surface area contact can beensured, which may ensure a low impedance across the junction.

The pressure assembly may include any mechanism known in the art thatmay provide a sufficient lateral force between the contact pads toensure a connection with the charge points (e.g., the contact pads maybe pinching together to receive the charge point). In some instances,features such as springs or elastics may be used in the pressureassembly. For example, as shown in FIG. 6A, the pressure assembly mayutilize a plurality of springs, that are connected to linkages and a barthat may allow a contact pad (71 a) to remain substantially parallel toanother contact pad (71 b), without directly contacting the othercontact pad.

FIG. 6B shows another view of a contact assembly (80), which may includeguiding features (81 a, 81 b), contact pads (82 a, 82 b), guiding pads(83 a, 83 b, 83 c, 83 d), a pressure assembly (84) which may exert aflexible pressure on one guiding feature (81 a), and a fixed assembly(85) which may fix another guiding feature (81 b) in place. The contactassembly (80) may also be connected to a spacing bar (86), and/or anyother structure (87), such as an arm, that may connect the contactassembly (80) to a charging mount (88).

FIG. 6C shows a close up of a pressure assembly in accordance with oneembodiment of the invention. The pressure assembly may include multiplesprings (90 a, 90 b) that may be connected to a bar (91) connected to aguiding feature (92 a). Linkages (93 a, 93 b) may also be provided,which may be connected to the bar (91) and/or guiding feature (92 a).The pressure assembly may keep the guiding feature (92) substantiallyparallel to another guiding feature (92 b). Furthermore, the pressureassembly or other features or components may prevent the conductive padsfrom contacting one another.

In some embodiments of the charger connection, there may be a cleaningbrush or mechanism which will clean the vehicle rooftop bars as thevehicle enters and/or leaves the charging arm assembly. This mayadvantageously provide an improved electrical connection.

FIG. 7A shows part of a charging chassis in accordance with anembodiment of the invention. A contact assembly (120) may be on aconnecting structure, such as an arm (121 a) and crossbar (121 b), thatconnects the contact assembly to a charging mount (122). The contactassembly may also be connected to a spacing bar (125). The contactassembly may be connected to the spacing bar and/or arm.

The contact assembly may include a fixed assembly (126), which may keepa guiding feature (124 b) in place. In some embodiments, a contactassembly may include at least one pressure assembly (127), and at leastone fixed assembly. Alternatively, a contact assembly may include aplurality of pressure assemblies. In some instances, a contact assemblymay include a plurality of fixed assemblies, although preferably, acontact assembly includes at least one pressure assembly.

The charging chassis may include a flexible connection (123). Theflexible connection may be between an arm and a crossbar. The flexibleconnection (123) may provide flexibility to the connecting structure arm(121 b) so that the contact assembly (120) on the arm (121 b) may moverelative to the charging mount (122) to accommodate the placement of oneor more charge point on a vehicle. For example, a vehicle may be drivento a charging station and placed so that one or more charge points isslightly offset from one or more contact assemblies. Guiding features(124 a, 124 b) of a contact assembly may capture a charge point of avehicle, and the flexible connection (123) may enable to the contactassembly to shift to follow the path of the vehicle. The flexibleconnection (123) may allow the contact assembly (120) to shiftsubstantially perpendicularly with respect to the direction of thevehicle travel. The contact assembly may be shifting laterally orhorizontally. Thus, if a vehicle were driven beneath a charging station,a flexible connection may enable flexibility within the connectionstructure that may enable one or more contact assemblies to movesideways relative to the vehicle to capture and contact one or morecharge point of the vehicle.

FIG. 7B shows an example of a flexible connection of a connectingstructure. The flexible connection may have any design that may provideflexibility to a connecting structure including springs, elastics,hinges, linkages, pivot points, pneumatic devices, weights, gears,hydraulics, or any other structure for flexible connection. For example,springs (130 a, 130 b) may be provided that may enable a portion of aconnecting structure to move laterally. A bar (131) of a connectingstructure may slide sideways with respect to a fixed portion of theconnecting structure (132). The portion of the connecting structure maymove laterally, which may enable one or more contact assembly to movelaterally to capture a charge point of a vehicle. The flexibleconnection may enable contact assemblies to return to a center position,and may utilize springs, hydraulics, or gravity to recenter theconnection assembly after use.

In some embodiments, a flexible connection may be structured such that abar of a connecting structure may swing back and forth, which may allowa contact assembly to swing back and forth. For example, the bar mayswing back and forth if a pivot point or hinge is provided. Featuressuch as springs, elastic, hydraulics, or gravity, may be used to enablethe bar to swing back to its original position at rest. In otherembodiments, the flexible connection may be provided that may enable abar (131) to swing rotatably around a connecting structure (132). Forexample, the bar may pivot a little around the connecting structure,which may enable a contact assembly at the end of the bar to movevertically with respect to the connecting structure. In someembodiments, there may be some give between the bar and the connectingstructure that may result in limited vertical movement of the contactassembly.

Vehicles

The vehicle can comprise two contact plates positioned on a top surfaceof the vehicle. The vehicle can comprise two bars attached to the roofof the vehicle. In some embodiments of the invention, the two bars areconductive and function as contact plates for establishing a connectionbetween the vehicle and a charging station. The two bars can be copperbars or any other type of conductive material. Other types of conductivematerial may include but are not limited to copper, aluminum, silver,gold, or alloys or combinations thereof, or may be plated/clad with aconductive material. In some instances, the bars may be formed of thesame materials, while in others, different materials may be utilized fordifferent bars. The bars may be formed of materials that may beresistant to corrosion. Furthermore, the bars may be formed of materialsthat are slippery or high in lubricity. In some embodiments of theinvention, the bars are similar in fashion to a luggage rack on an SUV.The two bars or contact plates can extend in a direction that isparallel to a direction of vehicle movement. As shown in FIG. 1, FIG. 2,and FIG. 3, the two bars (10, 12) can establish contact with a chargingconnection anywhere along the length of the bars. The orientation of thebars can reduce the need to align the vehicle in a forward or backwarddirection prior to charging the vehicle.

There may be mechanical and/or electrical protective devices on boardthe vehicle to isolate conductive paths during non-contact situations.Such devices may be configured to allow energy flow only after receivingan electronic message (wireless, proximity switched contact, and/ormanual trigger) or via direct mechanical activation.

The bars may also be installed at a prescribed gap height above thevehicle roofline to ensure any pooled water and/or other temporary orpermanent conductive matter is kept at an appropriate dielectric gapheight relative to the voltage differential.

The vehicle may have a gauge or screen on the dash to inform a driver ofthe vehicle as to the state of charge of the vehicle. The vehicle cancomprise a display for indicating that charging is in progress.

The vehicle can comprise a charge monitoring device that can communicatecharge status and vehicle rapid charge capabilities to other regionalcharging stations for characterization of energy availability. Thismonitoring system can be used for predictive modeling to estimate energyavailable at one or more charging stations on a route. The route can befixed, controlled using GPS guidance, or spontaneous. The monitoringsystem can be used to determine how much energy the vehicle can collectduring time available at a charging station. The vehicle can comprise asystem for predicting range based on charge status, energy availability,and predicted energy availability obtained by transfer of charge fromupcoming charging stations. In some embodiments of the invention, avehicle that is running behind schedule can skip or limit time spent ata charging station based on a prediction of energy required to reach ata subsequent energy station and/or the energy available at a subsequentenergy station. In other embodiments of the invention, a route can bemodified based on energy available at one or more charging stations.

In some embodiments of the invention, the vehicle comprises afast-charging energy storage device. The fast-charging energy storagedevice can be lithium titanate batteries or any other type of batteryknown to those skilled in the arts. The vehicle can be an electric busor electric hybrid bus comprising the fast-charging energy storagedevice.

FIG. 8 shows an example of a vehicle (140) with at least one contact bar(141). The vehicle may pass under a charging station, which may includea charging mount (142). A contact bar may pass through a contactassembly (143). The contact assembly may include a guiding feature (144)that may guide the contact assembly to receive the contact bar. Thecharging station may also include a connecting structure (145) that maybe flexible to enable lateral movement of the contact assembly, to allowthe contact assembly to receive the contact bar (141).

In some embodiments, one or more contact bar of a vehicle may be avertical plate with a rounded top. In some embodiments, this mayadvantageously allow for charging during icing conditions. In someembodiments, a contact bar may be shaped such that it has two or morecontact points with a vehicle. For example, as shown in FIG. 8, acontact bar (141) may have to contact points with a vehicle roof towardthe front and end of the contact bar. In other embodiments, a contactbar may have one contact with a vehicle roof. For example, an entirelength of a contact bar may be contacting a vehicle roof. Any number ofcontact points may be provided between a contact bar and a vehicle.

A contact bar may have any dimensions that may enable it to be attachedto a vehicle. For example, in some embodiments, a contact bar may beabout 1 cm, 5 cm, 10 cm, 20 cm, 30 cm, 50 cm, 80 cm, 100 cm, 120 cm, or140 cm long or longer. A contact bar may be about 0.5 cm tall, 1 cmtall, 2 cm tall, 3 cm tall, 4 cm tall, 5 cm tall, 7 cm tall, 10 cm tall,or 15 cm tall or taller. In some embodiments a contact bar may besufficiently tall such that there may be some flexibility in allowingfor a contact between the contact bar and a contact assembly of acharging station. For example, a contact bar may be sufficiently tall sothat the electrically conductive surfaces of a contact assembly maystill contact the contact bar even if there are some variations inheight, such as through bumps in the road, or different vehicle heights.

A contact bar may also have any thickness. For example, a contact barmay be about 0.2 cm thick, 0.5 cm thick, 0.7 cm thick, 1 cm thick, 1.5cm thick, 2 cm thick, 3 cm thick, 4 cm thick, 6 cm thick, or thicker. Acontact bar may be sufficiently thick such that when it passes between acontact assembly, both sides of the contact bar may contact guidingstrips of the contact assembly, preferably along electrically conductivesurfaces of the guiding strips. A contact may also be sufficiently thicksuch that when the contact bar passes between the guiding strips, asufficient amount of pressure is exerted on the contact bar to ensure astrong electrical connection, and a lowered impedance. The amount ofpressure may also be sufficient to ensure that the entire electricallyconductive surface area is contacting the contact bar, and not just aportion of the surface. Preferably, the thickness of the contact bar isa little greater than the space between the electrically conductivesurfaces of a contact assembly when at rest. This may ensure that theguiding strips of a contact assembly may sufficiently grip, press,squeeze, clamp, or hold a contact bar to provide a sturdy electricalcontact, while still allowing the contact bar to slide between theguiding strips.

Two or more contact bars may also be spaced apart on the roof of thevehicle. The contact bars may be spaced at any desired distance apart.For example, the contact bars may be spaced about 5 cm, 10 cm, 15 cm, 20cm, 25 cm, 30 cm, 35 cm, 40 cm, 45 cm, 50 cm, 60 cm, 70 cm, 80 cm orgreater or lesser apart. Preferably, the contact bars are substantiallyparallel to one another.

Methods

Transit buses can operate on a repetitive route system whereby the busrepeats its route at least every hour. As such, it passes the transitbus can pass a common point on an hourly basis and wait at that pointfor a cue to repeat the route. This can involve a wait of 10 to 20minutes in many cases. The methods of the invention provide for atransit bus that can utilize the wait time to charge the transit bus.The transit bus can comprise a fast charging energy storage device thatcan completely recharged in 10 minutes. In some instances, the transitbus can be completely or substantially (e.g., more than 75%) chargedwithin 5 minutes, 3 minutes, 2 minutes, or 1 minute. The fast chargingenergy storage device can be lithium titanate batteries or one ofseveral other battery chemistries.

In some embodiments of the invention, an energy storing device is onlypartially charged. Partially charging the energy storing device canincrease the life of the energy storing device by reducing the amount ofcharge transferred to the energy storage device during a single chargingprocedure. For example, an electric transit bus designed in accordancewith the invention described herein can average 11 to 13 miles per hourand consume approximately 1.5 to 3.0 kWh/mile. If the electric transitbus comprises an energy storing device with approximately 56 kWh ofcapacity, the electric transit bus can contain sufficient energy topropel the electric transit bus for approximately two to four hourswithout charging depending on driving application. That can allow forthe electric transit bus to run indefinitely with an hourly charging ofapproximately 25% of the capacity of the energy storing device. Thischarging procedure can increase the life of the energy storing devicerelative to a charging procedure that charges the energy storing devicefrom a completely drained state.

In some embodiments of the invention, a vehicle is charged bypositioning the vehicle under a charging station. The charging stationcan comprise a charging connection that is engaged by adjusting theposition of the charging connection. A control device in the vehicle canbe used to transmit instructions to the charging station and/or thecharging connection to establish an electrical connection between thecharging connection and the vehicle.

In some embodiments of the invention, the charging connection maycomprise a pair of contact assemblies with a known distance between themthat correspond to the distance between the charge points on the roof ofthe vehicle. These charge contacts can use a system to return them to acenter position that may utilize springs, hydraulics, or gravity torecenter the connection assembly after use.

In one example, the contact assembly may comprise conductive pads withguides to ensure that the assembly moves laterally or vertically withrespect to the direction of travel of the vehicle. To reduce complexity,the entire assembly may be energized if the support structure for theassembly can insulate voltages greater than the transmitted voltage. Thecontact pads may be metallic or non-metallic conductive pads and may ormay not be replaceable. A preferable method would be to have replaceablepads that can be changed when the conductive portion is damaged or used.By using a spring contact and a large surface area with respect to theamount of current transferred, the assembly can ensure a low impedanceacross the junction. In some embodiments, guidance into charge clampingdevices can be accommodated by electronic guidance device aligned bylaser or similar detection devices.

The vehicle and/or energy storage controls system may be able to monitorvehicle route timetable performance. If there is excess time availablefor recharge, the controls systems can elect to reduce charger powerand/or current to match the available break time in the route. As suchthere may be an increase in efficiency and system lifetime as a resultof modulated charging performance.

In some alternative embodiments, a charging station may also function asa discharger. For example, if a vehicle has a large amount of storedenergy (e.g., in an on-board battery or energy storage unit), it may bedesirable to discharge the vehicle somewhat, and transfer that energy toan energy storage unit of a charging station, or to provide it to autility. A charging station may be able to operate both to charge anddischarge a vehicle.

The systems and methods may utilize or incorporate any methods,techniques, features or components known in the art or previouslyutilized. See, e.g., U.S. Pat. No. Re 29,994; U.S. Pat. No. 3,955,657;European Patent Application No. EP 2 014 505 A1; European PatentApplication No. EP 1 997 668 A1; PCT Publication No. WO 2008/107767 A2;U.S. Patent Publication No. 2008/0277173; PCT Publication No. WO2009/014543, which are hereby incorporated by reference in theirentirety.

It should be understood from the foregoing that, while particularimplementations have been illustrated and described, variousmodifications can be made thereto and are contemplated herein. It isalso not intended that the invention be limited by the specific examplesprovided within the specification. While the invention has beendescribed with reference to the aforementioned specification, thedescriptions and illustrations of the preferable embodiments herein arenot meant to be construed in a limiting sense. Furthermore, it shall beunderstood that all aspects of the invention are not limited to thespecific depictions, configurations or relative proportions set forthherein which depend upon a variety of conditions and variables. Variousmodifications in form and detail of the embodiments of the inventionwill be apparent to a person skilled in the art. It is thereforecontemplated that the invention shall also cover any such modifications,variations and equivalents.

1-37. (canceled)
 38. A charging system for an electric bus, comprising:a charging station including at least a pair of charging electrodes, thepair of charging electrodes including (a) a linear first electrodeextending along a first longitudinal axis and (b) a linear secondelectrode extending along a second longitudinal axis, wherein the firstelectrode and the second electrode are spaced apart from each other andarranged such that the first longitudinal axis and the secondlongitudinal axis extend along a single straight line; at least a pairof charge-receiving electrodes positioned on a roof of the electric bus,the pair of charge-receiving electrodes including (c) a linear thirdelectrode extending along a third longitudinal axis and (d) a linearfourth electrode extending along a fourth longitudinal axis, wherein thethird electrode and the fourth electrode are arranged such that thethird longitudinal axis and the fourth longitudinal axis are parallel toeach other and transverse to the first longitudinal axis and the secondlongitudinal axis, and wherein the first electrode is configured tocontact the third electrode and the second electrode is configured tocontact the fourth electrode during charging of the electric bus; and apositioning device configured to adjust a distance between the pair ofcharging electrodes and the pair of charge-receiving electrodes toestablish electrical connection therebetween.
 39. The charging system ofclaim 38, wherein the pair of charging electrode are suspended above theroof of the electric bus.
 40. The charging system of claim 38, whereinthe positioning device is configured to move the pair of chargingelectrodes towards the pair of charge-receiving electrodes to makeelectrical contact therebetween.
 41. The charging system of claim 40,wherein the positioning device is further configured to move the pair ofcharging electrodes away from the pair of charge-receiving electrodesafter charging of the electric bus.
 42. The charging system of claim 38,wherein the third electrode and the fourth electrode extend parallel toa length direction of the electric bus.
 43. The charging system of claim42, wherein the third longitudinal axis and the fourth longitudinal axisare symmetrically positioned about a center line of the roof thatextends along the length direction of the electric bus.
 44. The chargingsystem of claim 38, wherein the third electrode and the fourth electrodeare spaced upwards from the roof of the electric bus.
 45. The chargingsystem of claim 38, wherein the third electrode and the fourth electrodeare attached to the roof proximate a front end of the electric bus. 46.The charging system of claim 38, wherein each electrode of the pair ofcharging electrodes includes a length between about 50-80 cm.
 47. Thecharging system of claim 38, wherein the third longitudinal axis and thefourth longitudinal axis are separated by about 50-80 cm.
 48. Thecharging station of claim 38, wherein a total number of chargingelectrodes is equal to a total number of the charge-receivingelectrodes.
 49. The charging system of claim 38, wherein the pair ofcharge-receiving electrodes are located above front wheels of theelectric bus.
 50. A charging system for an electric bus, comprising: acharging station including at least a pair of charging electrodes, thepair of charging electrodes including (a) a linear first electrodeextending along a first longitudinal axis and (b) a linear secondelectrode extending along a second longitudinal axis, wherein the firstelectrode and the second electrode are spaced apart from each other andarranged such that the first longitudinal axis and the secondlongitudinal axis extend along a single straight line; and at least apair of charge-receiving electrodes positioned on a roof of the electricbus, the pair of charge-receiving electrodes including (c) a linearthird electrode extending along a third longitudinal axis and (d) alinear fourth electrode extending along a fourth longitudinal axis,wherein the third electrode and the fourth electrode are arranged suchthat the third longitudinal axis and the fourth longitudinal axis are(i) parallel to each other, (ii) positioned symmetric to a center lineof the roof that extends along a length direction of the electric bus,and (iii) transverse to the first longitudinal axis and the secondlongitudinal axis.
 51. The charging system of claim 50, wherein thecharging station further includes a positioning device configured todecrease a separation distance between the pair of charging electrodesand the pair of charge-receiving electrodes to make electrical contacttherebetween, and increase the separation distance to break theelectrical contact after charging.
 52. The charging system of claim 50,wherein the third electrode and the fourth electrode extend over frontwheels of the electric bus.
 53. The charging system of claim 50, whereineach electrode of the pair of charging electrodes has a length betweenabout 10-100 cm.
 54. The charging system of claim 50, wherein the thirdlongitudinal axis and the fourth longitudinal axis are separated byabout 10-80 cm.
 55. A method of charging an electric bus at a chargingsystem, the charging station including a plurality of chargingelectrodes, the plurality of charging electrodes including at least (a)a linear first electrode extending along a first longitudinal axis and(b) a linear second electrode, spaced apart from the first electrode,and extending along a second longitudinal axis, wherein the firstlongitudinal axis and the second longitudinal axis extend along a singlestraight line, and the electric bus including on its roof a plurality ofcharge-receiving electrodes, the plurality of charge-receivingelectrodes including at least (c) a linear third electrode extendingalong a third longitudinal axis and (d) a linear fourth electrodeextending along a fourth longitudinal axis, wherein the thirdlongitudinal axis and the fourth longitudinal axis are (i) arrangedparallel to each other, (ii) spaced apart from each other, and (iii)arranged transverse to the first longitudinal axis and the secondlongitudinal axis, the method comprising: moving the plurality ofcharging electrodes of the charging station towards the roof of theelectric vehicle such that the first electrode electrically contacts thethird electrode and the second electrode electrically contacts thefourth electrode; activating charging of the electric bus by directingcurrent from the charging station to the electric bus; and moving theplurality of charging electrodes away from the roof of the electric busafter the charging.
 56. The method of claim 55, wherein moving theplurality of charging electrodes of the charging station towards theroof of the electric bus includes moving the plurality of chargingelectrodes towards the roof when the electric bus is positioned belowthe plurality of charging electrodes.
 57. The method of claim 55,further including receiving a signal indicative of electrical contactbetween the first electrode and the third electrode prior to activatingthe charging.
 58. An electric bus, comprising: a roof; and a first railand a second rail attached to the roof, wherein the first rail and thesecond rail are arranged parallel to each other and are positionedsymmetrically about a center line that extends along a length of thebus, and wherein each of the first rail and the second rail extends froma location above a front wheel of the electric bus towards a rear wheelof the electric bus; wherein the first rail includes a first electrodeand second rail includes a second electrode, and wherein each of thefirst electrode and the second electrode are configured to separablycontact different charging electrodes of a pair of charging electrodesof a charging station to charge the electric bus, the pair of chargingelectrodes being arranged such that (a) the different chargingelectrodes are electrically isolated from each other, and (b) alongitudinal axis of each of the different charging electrodes extendalong a single straight line arranged transverse to the first rail andthe second rail.
 59. The electric bus of claim 58, further including atransmitter configured to send a signal to the charging station as theelectric bus approaches the charging station.
 60. The electric bus ofclaim 58, further including a display configured to indicate thatcharging is in progress.
 61. The electric bus of claim 58, wherein alength of the first rail and the second rail is between about 1-140 cm.62. The electric bus of claim 58, wherein a height of the first rail andthe second rail is between about 0.5-15 cm.
 63. The electric bus ofclaim 58, wherein a width of the first rail and the second rail isbetween about 0.2-6 cm.
 64. The electric bus of claim 58, wherein aspacing between the first rail and the second rail is between about 5-80cm.
 65. The electric bus of claim 58, wherein the bus is a transit bus.66. The electric bus of claim 58, wherein the first rail and the secondrail are attached to the roof above the front wheels.
 67. The electricbus of claim 58, wherein an entire length of the first rail and thesecond rail contacts the roof.